Method of crimping yarn



Feb, 1967 D. A. E. MATTINGLY 3,302,264

METHOD OF CRIMPING YARN Original Filed Nov. 28, 1962 3 Sheets-Sheet 2 Denis A'LBEKTEDLMKD MflTTmaLy Feb 7, 1%?- D. A. E. MATTINGLY 3,302,264

METHOD OF CRIMPING YARN 3 Sheets-Sheet 5 Original Filed Nov. 28, 1962 35M 16 ALBEET EDUHRD MHTTING-Ly United States Patent 3,302,264 METHOD OF CRIMIING YARN Denis Albert Edward Mattingly, London, England, assignor to The Klinger Manufacturing Company Limited, London, England, a British company Original application Nov. 28, 1962, Ser. No. 240,551, now Patent No. 3,212,157, dated Oct. 19, 1965. Divided and this application May 28, 1965, Ser. No. 470,954 7 Claims. (Cl. 28-72) This application is 'a division of copending application Serial No. 240,551, filed November 28, 196?, now US. Patent No. 3,212,157, and entitled Crimping Apparatus.

This invention relates to a yarn bnnching method for yarns which are capable of being bunched after being raised to an appropriate temperature, and is applicable inter alia to the bnnching of nylon 66, and which method is of the kind involving moving yarn through a bnnching zone which is bounded by a part of a periphery of a rotatable wheel so that the yarn bunched in said zone clings to the wheel and moves with it out of the bunching zone and drawing the yarn off the wheel and winding it on a take-up spool or the like.

The method also involves heating the yarn prior to its entry into the bnnching zone.

A feature of the invention resides in tensioning the yarn while being heated prior to its entry into the bnnching zone.

The degree of tension may be such as to draw the yarn i.e. permanently stretch it.

The invention includes within its scope a method of bnnching yarn which consists first in tensioning or drawing the yarn while subjected to heat and then passing the yarn through a bnnching zone where it is again heated while being bunched.

It will be appreciated that the yarn requires to be brought to a certain physical condition sometimes referred to as set in'order that bnnching may be permanent. The method of bnnching according to the present invention is characterized in that the yarn is preheated with a required degree of shrinkage according to the properties of the crimp required before passing to the bnnching zone where it finally acquires the required strength of crimps i.e. degree of resilience by a second heat treatment.

Other features are set out in the following description and claims which description is of two embodiments of the invention, reference being made to the accompanying diagrammatic drawings in which:

FIGURE 1 is a side elevation of a part of the aforesaid wheel having a portion of its periphery projecting into a groove in an arcuate member which in its turn is arranged to project into a bight between two feed rollers (not shown);

FIGURE 2 is a section on the line 2-2 of FIGURE 1, the rollers being shown in chain line;

FIGURE 3 is a part perspective view of a preferred form of grooved member for accommodating the periphery of the wheel and also showing the mechanism for driving the rollers and for heating and tensioning the yarn before being bunched;

FIGURE 4 is a vertical section through a part of said grooved member shown in FIGURE 3; and

FIGURE 5 is a side view looking in the direction of the arrows 55 of FIGURE 4.

Referring to FIGURES 3 to 5 the yarn to be bunched is drawn off a bobbin 62 by a pair of rollers 63 and passes over an arcuate heater 64 which is heated by an electrical resistance 65 and means 74 provided for controlling the temperature of the heater in order to obtain the required properties of the finished yarn.

The yarn then passes between another pair of rollers 19 arranged as close as possible to the heater although in 'ice FIGURE 3, for ease of illustration, the transmission for driving the rollers is shown between them and the heater. The rollers 19 are mounted on shafts geared together at 58 and one of the shafts is driven from a motor 59 by a transmission 60.

The rollers 63 are driven from the other of the shafts carrying the rollers 19 through a transmission. In the case where the yarn is to be tensioned and drawn While being heated the peripheral speed of the rollers 19 is about four times that of the rollers 63.

In the case where the yarn is to be tensioned without being drawn, the peripheral speed of the rollers 19 may be about the same as or only slightly greater than that of the rollers 63. The linear speed imparted to the yarn by the rollers and the temperature and time during which it is heated depends on the nature of the yarn, its denier, whether it is to be only tensioned or drawn and the properties it is to have when passing to the bnnching zone. The values of these factors for yarns including nylon 66, Perlon, Terylene, polypropylene lie between the following limits.

Temperature, C. -240 Time of heating, seconds .l.5 Linear speed of yarn, feet per minute 1000 to 1500 At these figures the length of the path on the heated body 64 over which the yarn passes may range between 1.7 feet to 12.75 feet. For the longer lengths the yarn may be constrained to move by pegs or grooves in a zig zag fashion over the heated body.

In certain instances the rollers 63 can be dispensed with and the required shrinkage will be controlled by the speed of the yarn related to the length and temperature of the heater 64.

Arranged above the rollers 19 is a disc-like wheel 14 of small axial width having a toothed periphery 24a which Wheel rotates about an axis parallel to the axes of rotation of the rollers 19 and offset from a tangential plane common to the two rollers.

A part of the periphery of the wheel projects into a groove 12 formed in an arcuate metal element 10 provided with electric heating elements, not shown. The lower extremity of the arcuate element has secured to it a wedge shaped portion 18 which projects into the bight between the two rollers 19. The portion 18 is recessed at 16 to accommodate parts of the rollers 19 which are of small axial width (as best seen in FIGURES 4 and 5).

A hole 21 is arranged to extend from the smaller end of the wedge-shaped part and is widened at its upper end Where it meets the arcuate groove 12. One side wall of the hole is convexly curved at 70 so as to merge with the groove. A plate 71 is secured to the other side of the member and substantially closes the end of the groove but is slotted at 72 so as to permit the passage of the toothed periphery 24a of the wheel 14.

The smaller end of the wedge shaped part is spaced away from the closest point of approach of the two rollers so as to provide a small closed space where bunching may commence. It will be seen that the bight between the two rollers and the general axis of the hole 21 lie on a line at right angles to the plane in which axes of the rollers lie and which line is offset from the axes of rotation of the wheel 14. The said line, however, may intersect said axis of rotation. Also the general axis of the hole 21 may be inclined to a line passing through the axis of the wheel 14 into the bight between the rollers 19.

The tooth-ed periphery of the wheel gathers up the bunched y-arn moving it along the groove in the arcuate element which encloses the bunched yarn and heats it so as to bring it to its final required state.

The shaft 15 (FIGURE 1) of the wheel 24 is driven from the motor 59 through a transmission 67 including a gear box 73 so that the peripheral speed of the wheel 14 is less than the peripheral speed of the rollers 19 and in the case where the hole has a mean diameter of about 7 of an inch the ratio of the peripheral speed of the wheel to the peripheral speed of the rollers is between about one to one hundred and twenty and one to four hundred and sixty according to-the nature of the yarn and the form required.

In one example 410 denier nylon 66 yarn having 68 filaments, each filament being of tri-lobular cross-section, was bunched, the yarn entering the rollers 19 at 1000 feet per minute. The heater 64 was a 220 C. and had an effective length of 4 feet and the arcuate element was at 200 C.

The rollers 19 were 1% inches in diameter and rotated at 2170 revolutions per minute. The Wheel 14 was 5 inches in diameter and rotated once every 0.37 minute.

In a second example the conditions were as in the first example but the wheel 14 rotated once every 0.3 minute. he yarn received a less number of crimps per inch than in the first example.

In a third example the conditions were the same as in the second example but the yarn was 540 denier and each filament was of circular cross-section. The yarn received a greater number of crimps per inch than did the yarn in the second example.

In a fourth example the conditions were the same as in the first example except that the yarn was of 1040 denier and the wheel 14 rotated once every 0.17 minute. The yarn received a greater number of crimps per inch than did the yarn in the second example.

In a fifth example the conditions were the same as in the first example but the yarn was 250 denier Terylene having 48 filaments of circular cross-section. The heater 64 was at 180 C. and the arcuate element was at 180 C. The wheel 14 rotated once every 0.16 minute. The yarn received more crimps per inch than did the yarn in the second example.

In these five examples the rollers 63 rotated at the same speed as the rollers 19.

In a sixth example the conditions were the same as in the first example but the rollers 63 were omitted and the heater 64 had an effective length of 12 feet. The yarn produced had the same number of crimps per inch as the yarn produced by the first example but the former yarn contracted less than the latter yarn when allowed to contract freely from a straight condition.

A yarn similar to the yarn made by Example 6 was made by using the same conditions as in Example 6 with the heater 64 having an effective length of 4 feet, the wheel rotating once every 1.11 minutes and the speed of the yarn being 333.3 feet per minute.

The yarn after leaving the wheel 14 passes through a tensioning device 68 to winding mechanism 69 which may be driven from the motor 59 through a transmission prefer-ably embodying means which maintain the speed of winding constant with respect to the rate at which bunching takes place, and which means form no part of the present invention.

In the arrangement shown in FIGURES 1 and 2 the axis of rotation of the wheel 14 is arranged to be transversely to and above the axes of rotation of the rollers 19 and parallel to a plane containing those axes. The part is in the form of an arcuate element and is for the most part rectangular in cross-section.

Instead of having a separate wedge-shaped part attached to its end as in FIGURES 3 to 5, its end is cross slotted at 20 to permit the entering of parts of the peripheries of the rollers 19 and the bottom of the slot'20 is wedge-shaped and bounded by arcuate faces 17 which enter the big-ht between the rollers 19.

The inner periphery of the arcuate element 10 is formed the shaft 15 which extends clear of the arcuate element- 10 and is driven in the manner described with reference to FIGURES 3 to 5. The side faces of the arcuate element 10 are provided with arcuate grooves 11 for accommodating electric heating elements (not shown).

A vho-le 21 extends from the bottom of the groove 12 and terminates at the narrow end of the bight between the rollers 19. The locality 22 where the disc-like rollers 19 most closely approach one another is disposed beyond the end of the hole 21. The peripheral speed of the disc-like wheel 14 is arranged to be less than the peripheral speed of the disc-like rollers 19 and thus the yarn is bunched in the hole 21 and in the space 23 immediately beyond the hole.

The bunched yarn not only engages the periphery of the disc 14 which may be toothed as indicated at 24a but also flows around the side faces of the disc. The disc-like rotatable member 14 draws the yarn with it out of the upper end of the groove 12 as shown in FIGURE 1 and the bunched yarn then passes to a rotating package which accumulates it.

A guide block 83 extends into the bight between the rollers 19 on the opposite side thereof to the wheel 14 which block is provided with a hole 84 through which the yarn extends. The block may also be provided with an electric heating element (not shown).

The rollers 19 may also include electric heating elements.

Also the Wheel 14 might be heated. A thermos-tat may be associated with any of the heaters for maintaining the temperature constant.

With the above arrangements in which the peripheral speed of the rollers 19 is greater than the peripheral speed of the rollers 63 the yarn is prevented from shrinking and therefore from appreciably setting while passing over the heated body 64 and is only allowed to set or complete its setting after passing between the rollers 19 into the groove 12 and while on the wheel 14 within the groove. The yarn being a comparatively poor conductor and radiator of heat will carry its heat with it to the bunching zone where it is no longer under tension.

I claim:

1. A method of crimping yarn having at least a thermoplastic component, said method comprising the steps of preheating the yarn to soften the thermoplastic component, introducing the softened yarn into a crimping zone, surrounding the yarn in the crimping zone with stationary means from the entry end to the discharge end thereof for a relatively short distance in the lengthwise direction of the yarn and restricting passage of the yarn at the discharge end of the crimping zone to thereby form a mass of crimped yarn, forcing the mass of crimped yarn to the discharge end of the zone, positively engaging the mass of yarn internally of the outer periphery thereof and along its entire length as it emerges from the discharge end of the zone and conveying the thus engaged yarn substantially without slippage from the crimping zone through a setting zone for a sufficient time to set the crimp in the yarn while substantially preserving the yarn in the configuration in which it was delivered from the crimping zone.

2. The method of claim 1 comprising heating said mass of yarn in said setting zone while simultaneously conveying same therethrough.

3. The method of claim 2 including subjecting the yarn to heat at a lesser temperature when passing through said setting zone than when preheating the yarn before the introduction thereof into said crimping zone.

4. The method of claim 3 wherein the yarn is nylon 66 and including preheating the yarn before the introduction thereof into the crimping zone by subjecting the yarn to a temperature of about 220 C. and heating the yarn during its passage through the setting enclosure by subjecting the yarn to a temperature of about 200 C.

5. The method of claim 1 including drawing the yarn simultaneously with preheating the yarn before introduction thereof into said crimping zone.

6. The method of claim 1, including drawing the yarn to an extent of about four times its undrawn length simultaneously with preheating the yarn before introduction thereof into said crimping zone.

7. A method of crimping yarn having at least a thermoplastic component, said method comprising the steps of heating the yarn to soften the thermoplastic component, introducing the softened yarn into a crimping zone, surrounding the yarn in the crimping zone with stationary means from the entry end to the discharge end thereof, forming a mass of crimped yarn by restricting yarn passage therein, forcing the mass of crimped yarn to the discharge end of the crimping zone and immediately, positively engaging the mass of crimped yarn internally of the outer periphery thereof and along its entire length as it emerges from the said crimping zone, and conveying the thus engaged yarn substantially without slippage from the crimping zone through a confined setting zone, heating the'yarn during its passage through the setting zone, whereby the crimp is set in said yarn during its travel through the confined setting zone, while substantially preserving the yarn in the configuration in which it was delivered from the crimping zone, and then withdrawing the yarn from the leading end of the mass.

References Cited by the Examiner UNITED STATES PATENTS 2,686,339 8/1954 Holt 2872 X 2,734,228 2/1956 Hay 2872 X 2,914,810 12/1959 Robinson et al 2872 X 2,949,659 8/1960 Heijnis et a1. 3,023,481 3/1962 Scragg 2872 X 3,027,619 4/ 1962 List et a1 2872 X 3,111,740 11/1963 Stanley 28-72 X 3,146,512 9/1964 Heijnis 2872 X 3,153,272 10/1964 Mattingly 2872 X 3,174,208 3/1965 Saito et a1. 2872 FOREIGN PATENTS 230,339 9/1960 Australia. 316,685 12/ 1956 Switzerland.

ROBERT R. MACKEY, Primary Examiner. 

1. A METHOD OF CRIMPING YARN HAVING AT LEAST A THERMOPLASTIC COMPONENT, SAID METHOD COMPRISING THE STEPS OF PREHEATING THE YARN TO SOFTEN THE THERMOPLASTIC COMPONENT, INTRODUCING THE SOFTENED YARN INTO A CRIMPING ZONE, SURROUNDING THE YARN IN THE CRIMPING ZONE WITH STATIONARY MEANS FROM THE ENTRY END OF THE DISCHARGE END THEREOF FOR A RELATIVELY SHORT DISTANCE IN THE LENGTHWIDE DIRECTION OF THE YARN AND RESTRICTING PASSAGE OF THE YARN AT THE DISCHARGE END OF THE CRIMPING ZONE TO THEREBY FORM A MASS OF CRIMPED YAN, FORCING THE MASS OF CRIMPED YARN TO THE DISCHARGE END OF THE ZONE, POSITIVELY ENGAGING THE MASS OF YARN INTERNALLY OF THE OUTER PERIPHERY THEREOF AND ALONG ITS ENTIRE LENGTH AS IT EMERGES FROM THE DISCHARGE END OF THE ZONE AND CONVEYING THE THUS ENGAGED YARN SUBSTANTIALLY WITHOUT SLIPPAGE FROM THE CRIMPING ZONE THROUGH A SETTING ZONE FOR A SUFFICIENT TIME TO SET THE CRIMP IN THE YARN WHILE SUBSTNATIALLY PRESERVING THE YARN IN THE CONFIGURATION IN WHICH IT WAS DELIVERED FROM THE CRIMPING ZONE. 